Image transfer apparatus



Dec. 3, 1963 J. M. FLUKE v IMAGE TRANSFER APPARATUS y 2 Sheets-Shet lFiled June 12. 1961 y &

-l wl- Dec. 3, 1963 J. M. FLUKE IMAGE TRANSFER APPARATUS 2 Sheets-Sheet2 Filed June 12, 1961 conf/ms mr M/ve 010346 l naamw/roman INVENTOR.Jffffm N.

BY l M l United States Patent Oil ice arrasa; Patented Dec. 3, 19533,112,685 n/raoa raANsrnn Armarios lJefferson M. Fluke, 1811 16th W.,Kirkland, Wash.,

iisighnor of one-half to Ralph D. Bennett, Kirkland,

Filed June l2, 1961, Ser. No. 116,43@ 14- Clairns. (Cl. 9S-39) ence toits presently preferred embodiment as applied to y the transfer ofphotographic images from coated paper carriers to coated aluminum' sheetcarriers lfor use in photo-offset printing systems; however, -it will berecognized that certain modifications and changes therein with respectto details and with respect to applications may beV made withoutdeparting from the underlying essentials 'comprising the features of theinvention.

In previous devices for effecting image transfers between carriers,difficulty was experienced in achieving precise uniformity in the degreeof wetting and activation yof the carrier coatings by the developerliquid 'While moving the carriers `at a continuous and rapid rate intoprogressive mutually superposed relationship in passing through theapparatus. Also, the previous arrangements of carrier feeds and guidestogether with the means, usually an immersion bath container for thedeveloper liquid, made visual inspection of the cooperating carriers fordetermination of relative positioning most difficult.y

A broad object of this invention is to overcome these difficulties andmore specifically to provide a compact,

' efficient and economical apparatus to this end.

Still another object is an improved image transfer apparatusincorporating feed Iand :guide elements arranged for compactness and foreasy determination and Iadjustment of relative positioning ofthecarriers.

A further object is apparatus Which incorporates in combination thereinan improved means rfor spreading developer liquid while guiding acarrier, and more specically which is capable of spreading and flowingdeveloper liquid uniformly over the coated surface of one carrier underpressure which insures uniform wetting and activation of itsphotographic coating :despite variations or spottiness in its acceptanceof such liquid, while also providing related arrangements for achievinguniform wetting of the other carrier 'with the developer liquid.

In accordance with this invention as herein disclosed, one carrier,preferably the image-bearing carrier since it is usually the morecritical of the two carriers as to lcoating activ-ation, is fedtangentially to the upper periphery of a driven guide roller to advancethrough the guide space between the roller and a conformably curvedguide shoe which serves also as ra ydeveloper applicator to whichdeveloper liquid under pressure is supplied by .a recirculation pump soas to insure uniform` spreading and flow of developer liquid over thecarrier surface. Liquid pressure also increases feed traction of theguide roller on the carrier. The second carrier, in the examplecomprising the image-receiving carrier or coated aluminum sheet, is fedkto the lower periphery of the guide roller with the direction ofrotation thereof at la location directly lbeneath the applicator shoe,so that excess developer liquid which runs down from theshoe `onto thesecond carrier as it converges with the first carrier rounding the guideroller, puddles there and supplements the wetting of the carriercoatings. The two lthen mutually superposed carriers uniformly wetted attheir interface pass between the guide roller and a squeegee rollerpressing against it. A liquid receiver beneath the cooperating rollersand shoe catches the run-off and holds it Afor the recirculation pump.Preferably the second feed comprises a driven roller also which isdrivenby the same power means as that driving the guide roller,y throughseparate power transfer overrunning clutches permitting independentmanual speed-up 0r advance rotation of keither suc-h roller in order toad- Vance the leading edge of either carrier relative to the othercarrier as they approach convergence, and thereby permit positionallyindexing the two carriers relatively.

These arrangements, particularly the preferred embodiment wherein thevmost desirable `features ofthe invention rare combined Vfor theillustrative application, provide -a precision, economical, lrapidproduction, compact, easily operated and highly reliable machineaccording to the foregoing objectives.

These an-d other features, objects and advantages of the invention willIbecome more fully evident from the following description thereof byreference to the accompanying drawings.

FIGURE 1 is a perspective view of the illustrative embodiment with partsbroken aW-ay to show detailsv of construction.

FIGURE 2 is a longitudinal apparatus.

FEGURE 3 is an enlarged longitudinal section-al View as in FIGURE 2,with the parts in operation.

FIGURE 4 is an end View of the lapparatus with parts broken away insection to show construction.

FIGURE 5 is an enlarged sectional detail of the driven guidevrrollermechanism as yviewed in a longitudinal sectional plane.

Referring to the drawings, a readily removable upper assembly di)comprises the frame side plates 12 and 14 which are interconnected byand carry various other parts. The upper assembly 10 rests on a lowerlassembly 16 comprising the pedestal or base 18 'having upstanding' sidesectional View of the Y brackets Ztl and 22 thereon provided withhorizontally extending upright flanges 24 notched at 24a to receivelocating pins 26 carried by the respective upper assembly plates 12 land14.

Horizontal tie rods 28 maintain the side plates 12 and 14 in verticallydisposed parallel relationship, as do the oppositely inclined feed pansor aprons 30 and 32, respectively, which at their opposite side edgesare bolted to the respective plates, as indicated at 34. The feed apron30, located generally above the feed apron 32, has its lower horizontaledge portion terminate just above and in tangential relationship to thedriven guide roller 36 in order to feed carrier sheets tangentiallybetween said roller and a cooperating presser roller 38 journaled foridling in the upper assembly frame. The lower edge portion of the secondand oppositely inclined feed chute 3:2V is tangentially directed aginstthe lower periphery of the driven guide roller 36 and has a curved loweredge portion 32a which extends conformably about the lower edge of theguide roller through a short arc beyond the point of tangency to leadthe mutually superposed carriers between such roller and a secondpresser roller 40, also an idler, bearin g upwardly against the lowerperiphery of the driven guide roller 36. Preferably the feeding ofcarriers on apron 30 to the guide roller is accomplished initially bysliding the carriers down the apron into the nip of rollers 3S and 35,from which point the carrier is advanced by frictional contact with thedriven guide roller 36. Carriers advanced along feed apron 32, however,are preferablyV fed positively to the guide roller 36 by means of adriven roller 42 cooperating with a presser roller 44 through a slot orslots 32h in the guide apron 32.

Each of the respective presser rollers 3S, 40 and 42 are spring urgedagainst their respective cooperating rollers by suitable mountingarrangements permitting some sliding movement of their support journalsin a direction toward and from the respective cooperating rollers, andby springs 4.5 which urge them against the latter.

Also part of the upper assembly is a power means preferably comprisingthe gear-head motor 46 mounted on frame plate 14 and having an outputshaft 46a upon which the spur gear 43 is fixed. This spur gear mesheswith similar gears 5t) and 52 which idle on one end of the respectivesupport shafts 54 and 56 of driven rollers 42 and 36. The ratios of gear48 to gear 50 and of gear 48 to gear 52 are such that the driven rollershave the same peripheral speed when driven by these gears throughseparate power transfer means comprising the overrunning clutches 58 and60, respectively. The latter are part of a carrier indexing arrangement.Each of these overrunning clutches comprises a toothed member, such as agear serving as a ratchet wheel fixed on the associated support shaft 54or 56, and a spring-kept pawl mounted on the associated idle gear toengage the ratchet wheel. These clutches represent one of varioussuitable types of overrunning clutch devices which can be used for thepurpose. To complete the indexing arrangement, a manual turn knob 62mounted on each of the roller support shafts 54 and 56, preferably atthe end opposite from the gearing, permits independent manualadvancement rotation of each roller for indexing adjustment of theindividual carriers being fed to the apparatus, without necessity fordisengaging gears.

An additional and vitally important element of the upper assemblycomprises the carrier guide and developer applicator shoe 62 which ispositioned adjacent the side periphery of driven guide roller 36 by endmounts 64 secured to the side plates l2 and 14, respectively. This guideshoe 62 is arcuately curved conformably to the peripheral curvature ofthe guide roller 36 and is spaced outwardly therefrom by a slightdistance affording clearance for passage of an image-bearing carrier Cbtherebetween after its emergence from between the rollers 36 and 38,plus a sufficient clearance over and above the thickness of the coatedcarrier Cb to permit free flow of a film of developer liquid throughthisinterface region as it is introduced therein under pressure. Preferablythe developer is introduced through an opening 62a formed in the shoe,which extends the length of the guide shoe at a location intermediateits upper and lower edges as shown. The surface of roller 36 supportsthe exible carrier sheet against the liquid pressure. Pressure of liquiddeveloper against the carrier further increases its frictional feedcontact pressure with the guide roller 36 so as to increase the positivefeed imparted to the carrier. The upper edge of the guide shoe 62extends nearly to the pressure roller 38 and serves to catch the leadingedge of a carrier Cb as it emerges from between the rollers 36 and 38.This upper edge has notches 62h at intervals along its length throughwhich pressurized developerV liquid escapes or is depressured so that itcannot spurt up against the roller 38. It isV desired to keep thisroller dry as possible so as to avoid predeveloping the carrier coating.The lower edge of shoe 62 is also provided with notches 62e at locationsalong its length, but for a somewhat different purpose. This purpose isto permit increased iiow and run-off of pressurized developer liquidthrough the space between the shoe and the drive roll 36, which flowwould otherwise be limited due to the flow resistance entailed in thedownward arcuate extent of shoe 62 serving to guide the carrier Cb intoconvergence with carrier Cr from feed guide 32.

Thus, pressurized developer liquid forced from opening 62a into andthrough the space between the carrier Cb and the guide shoe spills downinto the reentrant space just mentioned where it puddles and istemporarily retained as a means to supplementally wet theimage-receiving carrier Cr and to wet carrier Cb. Excess developerliquid, barred by the squeege roller 4b from removal with the 4departing carriers, runs out of the sides at the interface between themutually superposed carriers.

This excess liquid running down from the upper assembly is caught in areceiver tray 70 placed on the base 18 between the side members 20 and22. This receiver tray serves as a reservoir for developer liquid D. Amotordriven pump 72 mounted in this receiver tray draws from thereservoir and forces developer liquid through the tube 74 to the inlet62d of a distribution channel formation 62e formed, in communicationwith the opening 62a, on the back side of the arcuate shoe 62. The inlet62d is conveniently located at one end ofthe guide shoe 62 near the sideof the apparatus at which the pump 72 is stationed. From this inletlocation the guide shoe distribution channel 62e decreases progressivelyin cross section toward its opposite end so as to insure substantiallyuniform rate of discharge of developer liquid from the channel 62ethrough the opening 62a along its length despite pressure drop alongsuch length.

Preferably temperature control of the developer liquid in the suppiytray '79 is provided by suitable means comprising, for example, ahollow-wall tray construction affording a heat exchange chamber '760.through which temperature controlled liquid R may be circulated by meansof outside conduits 73 extending to and from a source of such liquid(not shown). Y

in operation of the apparatus, an image-bearing carrier sheet Cb isplaced on the apron 3) and an image-receiving carrier sheet Cr is placedon the apron 32, usually with the motor 36 deenergized. Pump 72 is inoperation to circulate liquid developer through the tube 74 and theinterface region between arcuate applicator-guide shoe 62 and theadjacent peripheral side of roller 36. Now, the rollers 38 and 42 arVindividually turned manually in order to advance the respective carriersinto appropriate superposed registry as they converge in the reentrantregion beneath the iower periphery of the guide roller 36. Thereupon theguide roller 36, and with it the driven roller d2, is placed inoperation by energizing the drive motor 46 in order to continue theprogressive advance of the now superposed carriers. As the carriersemerge from the space between the guide 32a and roller 36 they aresqueegeed under pressure exerted against the latter by the presserroller 40 so that they emerge and depart in a semi-dry state. Ifdesired, the motor 46 may be left in continuous operation along with thepump motor 72, and with a small amount of practice an operator mayaccomplish the correct registry of carriers through superimposing anynecessary increments of feed motion to one sheet or the other by simplyturning the appropriate manual turn knob of roller 36 or roller 4t2, aspermitted by the respective overrunning clutches described. In order topermit visual inspection of the relative positioning of the sheets, theapplicator-guide shoe 62 is preferably made of a transparent material sothat the leading edge of carrier sheet Cb may be observed as itapproaches convergence with the leading edge of carrier sheet Cr. Thearrangement of rollers and applicator shoe permit ready observation ofthe manner in which the carrier sheets meet.

These and other aspects of the invention will be recognized by thoseskilled in the art on the basis of the foregoing disclosure of thepresently preferred embodiment, which persons will also recognize thatthe invention is not necessarily confined to the illustrative details ofconstruction and application, except within the fair intended meaningsof the claims which follow.

I claim as my invention:

1. Image transfer apparatus comprising means to advance an image-bearingcarrier and an image-receiving carrier edgewise into progressivesuperposed contact one with the other along respective paths whichconverge together, said means including Va guide surface on which onecarrier is guided in approaching such convergence with the othercarrier, the guide surface being contacted i by `that face of said onecarrier which is opposite that contacted by the other carrier, developerliquid applicator shoe means disposed ciosely adjacent said guidesurface and conforming substantially in shape to and parallel with saidguidesurfaceto form a narrow passage theresaid one carrier and said shoemeans, yspreads out and flows over the carriertherein. l

2. Image transfer apparatus comprising means to` advance animage-bearing `'carrier and an image-receiving carrier edgewise 4intoprogressive superposed contact one with the other along respective pathswhich converge together, said means including a oonvexly curved guidesurface around which one carrier is guided in approaching suchconvergence with the other carrier, the guide surface being contacted bythat face of said one carrier which isk opposite that contacted by theAother carrier, developer liquid applicatormeans having a concavelycurved guide face extending parallel to and along said guide surface inclosely spaced relationship lforming an intervening passage for said onecarrier slightly thicker than the carrier itself, and means includingsaid applicator means, accumulator means to receive the overiiowtherefrom and a pump to deliver the accumulated developer liquid to saidpassage under pressure causing spreading and ow of the liquid uniformlythrough the interface between the applicator and said one carrier,thereby to wet the latter carrier and thereby also the other carrier asthe two carriers come together, said applicator means comprising acurved guide shoe which is apertured -to pass developer liquid to suchpassage at a location intermediate its relatively leading and trailingedges.

3. The image transfer apparatus defined in claim 2, wherein the guideshoe comprises a curved plate-like member having an elongated grooveextending in its guide face, across the breadth of the passagetransverse to the direction of carrier movement, said groove comprisingthe aperturing through which developer liquid ows to the passage.

4. The image transfer apparatus defined in claim 3, comprising ahorizontally disposed revolving roller providing said guide surface,airst feed for advancing said one carrier into tangential relationshipwith the upper periphery of the revolving roller in the direction ofmotion of such upper periphery, and a second feed for advancing theother carrier into tangential relationship with a point on the lowerperiphery of the revolving roller in the direction of motion `of suchlower periphery, the guide shoe being positioned adjacent the revolvingroller in the path of said one carrier ahead of the infeed point of thesecond carrier, whereby developer liquid from the shoe runs from saidpassage down lonto said other carrier as it approaches the revolvingroller.

5. The image transfer apparatus defined in claim 4, wherein 4the lowerand upper edge portions of the shoe have a succession of openings formedthereinalong the length thereof.y

6. The image transfer apparatus defined in claim 5, and a presser rolleroperatively associated with the revolvin ll n v i www rollers, at leastone of saiddrive means including a unidirectional coupling permittingseparate turning of one of therevolving rollers independently of theother in the direction of driven rotation, and thereby permittingindexing of one carrier relative to the other.y

7. Image transfer apparatus comprising means to advance an image-bearingcarrier and an image-receiving carrier edgewise into progressivesuperposed contact one with the other along respective paths whichconverge together, said means including a horizontal revolving rolleraround a side portion of which one carrier is guided in approachingconvergence with the other carrier, and means including a pump andy adistributor of developer liquid mounted adjacent said roller sideportion and conforming substantially in shape to and parallel with theperiphery of the roller so as to form an interface region therebetweenfor confinement of a layer of developer liquid spread out on thecarrier, said distributor thereby being operable under pressure fromsaid pump to spread developer liquid Y k on the exposed face of said onecarrier' as it advances around said side portion, the first-mentionedmeans including a rst feed for advancing said one carrier intotangential relationship with the upper periphery of the revolving rollerin the direction of motion of such upper periphery, and a second feedfor advancing the other carrier into tangential relationship with apoint on the lower periphery of the revolving roller in the direction ofmotion of such lower periphery. l

8`. rImage transfer apparatus comprising means to advance animage-bearing carrier and an image-receiving carrier edgewise intoprogressive superposed contact one with the other along respective pathswhich converge together, said meansincluding a horizontal revolvingroller around a side surface` of which one carrier is guided inrapproaching convergence with the other carrier, and further including aguide surface for the other carrier, and means including a pump and anarcuately curved distributor shoe conformed to and spaced a Vshortdistance from one of said surfaces to dene a passageway therebetween forthe individual carrier which is guided by the last-mentioned one of saidsurfaces and for a layer of developer liquid spread on said individualcarrier, and operable under pressure from said pump to spread developerliquid onV the exposed face of said individual carrier as it advancesthrough said passageway, the first-mentioned means including a firstfeed for advancing said one carrier into tangential relationship withthe upper periphery of the revolving roller in the direction of motionof such upper periphery, and

a second feed for advancing the other carrier into tangentialyrelationship with a point on the lower periphery of the revolving rollerin the direction of motion of such lower periphery. n

9. Image transfer apparatus comprising means to advance an image-bearingcarrier and an image-receiving carrier edgewise into progressivesuperposed contact one with the other along respective paths whichconverge together, said means including a horizontal revolving rolleraround a side surface of which one carrier is guided in approachingconvergence withthe other carrier, and further including a guide surfacefor the other carrier, and means including a pump and a distributor shoespaced a short.

distance from one of said surfaces to define a passageway therebetweenfor the individual carrier which is guided by the last-mentioned one ofsaid surfaces and operable under pressure from said pump to spreaddeveloper liquid on the exposed face of said individual carrier as itadvances through said passageway ts- H second feed, drive meansdrivingly interconnecting the revolving rollers to rotate at the sameperipheral speed, a power source, and drive means driving-ly connectingsaid power source to onek of the revolving rollers, at least one of saiddrive means including a unidirectional coupling permitting separateturning of one of the revolving rollers independently of the other inthe direction of driven rotation,'and thereby permitting indexing of onecarrier relaperiphery respectively of the guide roller, power means toyrotate the guide roller in one direction, a rst feed to advance onecarrier tangentially between the rst presser roller and guide rollerwith rotation of the latter, an arcuately curved guide shoe operativelyassociated with the side periphery of the guide-roller to pass said onecarrier therebetween as it emerges from between the guide roller andfirst presser roller, a second feed to advance the other 'carriertangentially between the second presser roller and guide roller withrotation of the latter, including guide means converging with the guideroller beneath said guide shoe, whereby the two carriers are advancedconvergingiy into superposed relationship and guided to the secondpresser roller, and means operatively associated Vwith the guide shoe toforce developer liquid under pressure through the space between the shoeand the irst carrier sucient to run down onto the second carrier as itconverges with the firstrcarrier, including a receiver for excessdeveloper liquid running from the carriers and a pump drawing from thereceiver to recirculate such excess developer liquid to the guide shoe.Y

12. The apparatus defined in claim 11, wherein the second feed includescooperating feed roller means one of which is driven, and separate powertransfer means from the power means to the driven feed roller Vmeans andto the guide roller, each including a unidirectional clutch meanspermitting independent' manual rotation `of the driven feed roller meansor guide roller selectively to ad- Vance either carriers leading edgetoward convergence` with the other carrier.

13. The apparatus defined in claim 11, wherein the guide shoe comprisesa curved plate having notched upper and lower edges, and a developerliquid feed channel extending generally horizontally across said plateintermediate said edges and in direct communication with the ReferencesCited in the file of this patent UNITED'STATES PATENTS 2,966,108 BogerDec. 27, 1960

1. IMAGE TRANSFER APPARATUS COMPRISING MEANS TO ADVANCE AN IMAGE-BEARINGCARRIER AND AN IMAGE-RECEIVING CARRIER EDGEWISE INTO PROGRESSIVESUPERPOSED CONTACT ONE WITH THE OTHER ALONG RESPECTIVE PATHS WHICHCONVERGE TOGETHER, SAID MEANS INCLUDING A GUIDE SURFACE ON WHICH ONECARRIER IS GUIDED IN APPROACHING SUCH CONVERGENCE WITH THE OTHERCARRIER, THE GUIDE SURFACE BEING CONTACTED BY THAT FACE OF SAID ONECARRIER WHICH IS OPPOSITE THAT CONTACTED BY THE OTHER CARRIER, DEVELOPERLIQUID APPLICATOR SHOE MEANS DISPOSED CLOSELY ADJACENT SAID GUIDESURFACE AND CONFORMING SUBSTANTIALLY IN SHAPE TO AND PARALLEL WITH SAIDGUIDE SURFACE TO FORM A NARROW PASSAGE THEREBETWEEN AND THROUGH WHICHSAID ONE CARRIER IS MOVED, WITH SAID PASSAGE BEING ONLY SLIGHTLY THICKERTHAN SAID ONE CARRIER, SAID APPLICATOR SHOE MEANS HAVING AN OPENINGTHEREIN COMMUNICATING WITH SAID PASSAGE AT AN INTERMEDIATE LOCATIONALONG THE EXTENT OF SAID GUIDE SHOE IN THE DIRECTION OF CARRIER MOVEMENTTHROUGH THE PASSAGE, AND PUMP MEANS CONNECTED TO SAID OPENING TO FORCEDEVELOPER LIQUID INTO SAID PASSAGE UNDER PRESSURE AND THEREBY CREATE APRESSURIZED FILM OF LIQUID WHICH INHERENTLY, BY REASON OF THE PRESSUREAND THE CONFINEMENT BETWEEN SAID ONE CARRIER AND SAID SHOE MEANS,SPREADS OUT AND FLOWS OVER THE CARRIER THEREIN.